Digital television (DTV) is a TV broadcasting system that processes a digital signal of 0 and 1 in all broadcasting stages such as production, edition, transmission, and reception, in contrast to an analog television that processes different signals according to the type of information. Conventional TV uses an analog method by which a signal is sequentially processed over time, thereby having a limit to providing sharp and clear pictures and sound and being limited in the number of channels.
A digital television receives video and audio signals from various external sources such as DVD players, personal computers (PCs), set-top boxes (STBs), and over-the-air broadcasting. In particular, DTV can receive both analog audio signals and digital audio signals at the same time.
A DTV system typically receives multiple audio signals over different channels (herein referred to as multi-channel audio signals) for which clock signals are not synchronized with each other. When a multi-channel audio analog-to-digital converter and a multi-channel audio digital-to-analog converter whose clock signals are not synchronized with each other are integrated into a single semiconductor chip, severe noise can occur in an audio signal band due to mutual interference between the clock signals.
When a multi-channel audio signal converting device is used, each channel typically has an asynchronous clock signal compared to the other channels, causing unwanted noise. Accordingly, when a multi-channel audio signal converter is used, the quality of signals may deteriorate.